I get that error when I try to click on my removable disk (E:). I am trying to use a USB MultiCard Reader/Writer. It said that the hardware already installed and everything, but somehow I can't get it to work. Does anyone have any idea what I should do? Thanks in advance.

sometimes if the driver is incorrect or incomplete that error will show when you have a memory card in the memory slot.
its may also happen if the card its self is not working the correct way.
i have seen memory cards work in one machine and not another because the card is breaking down.

if this card reader is on a laptop what is its make and model number and what windows are you running ?

two drivers are listed for that card reader under windows xp.
both should be loaded as the Texas Instruments is the interface chipset and one part of the reader and the Media Card Reader Driver adds secure digital (SD) and multimedia cards (MMC) parts.
why Hp have spilt it like that i don't know but best to load up both drivers as listed here.

right if that failed to work there is one other thing i can think off.
that card reader does not read micro sd cards on its own. just standard sd cards.
have you plugged it in to a adapter then in to the card reader?
if thats the case check the adapter is working.

the card reader may well not support micro SD cards, i will try and double check that up with HP later tonight to confirm that idea.

if thats the case you may have to connect the phone to the laptop by USB,
thats what i have to do with my own phone as my card reader has the same problems, however i will check up with HP first.

well thats pretty heavy reading so i will try and break this down to laymens terms.

there is two different mico sd cards The SD and SDHC
now both need a different adapter, from what i was reading they use a different pin config in order to work in a standard card reader.

in short you need to make sure the adapter you have supports your version of mico sd card.

even with the correct adapter there are still reports on the net saying they don't work in a full size card reader.
( i have the same problem with my memory stick pro duo )

this i think is going to drive you mad and the best way to transfer files from phone to computer and back again would be to use the usb cable and phone software for your mobile,
doing it that way is going to save you time and money trying to find a working adapter.